Milking Time Effect on Nutrients Level of Free Range Indigenous and Zero Grazed Exotic Cow Milk on Calcium, Magnesium, Potassium and Zinc in Kajiado County, Kenya

The purpose of this study was to determine whether the different milking time in a cow affects the nutrients levels in the milk. Milk is considered as balanced diet food with nutrients playing an important role in the body of a human being like calcium build and maintain strong bones and teeth, magnesiumhelps in muscular functions, potassium helps in blood pressure control, muscle and nerve function while zinc stimulates the activity of enzymes in the body, supports immune system, synthesize DNA and in wound healing.Nutrients levels were determined using analytical methodsAAS for analysis of calcium, magnesium and zinc and AES for analysis of potassium. Cow milk obtained in the morning and in the evening had different levels of nutrients in free range indigenous and zero grazed exotic cows. The results showed that in free range indigenous cow milk, nutrients are higher in the morning than in the evening except magnesium while in zero grazed exotic cow milk, the nutrients analysed are higher in the evening milk than the morning milk.Cow milk obtained in the morning from free range indigenous cows and that from evening from zero grazed exotic cows is the best to be taken. Keywords: AAS, AES, Cow, milk, nutrients levels

Assessment of the Impact of Effluents Discharge from Murang’a Town and Its Environs on the Water Quality of River Mathioya, Murang’a County, Kenya

Effect of effluents into rivers is of great economic, environmental and health concern. Chemical fertilizers are used extensively in modern agriculture, in order to improve yield and productivity of agricultural products. However, nutrients, leaching through the soil from agricultural activities, sewerage effluents and runoff from residential areas reaching river water resources are causing serious pollution. The purpose of this study was to determine the impact of effluent discharges on water quality of River Mathioya in Murang’a County, Kenya. Samples were collected upstream and downstream of Murang’a town along the Mathioya River. The pH, dissolved oxygen, electrical conductivity, total dissolved solid, total suspended solids and temperature were determined using the respective meters. Heavy metals were determined using flame atomic absorption spectrometry while sodium and potassium were determined using flame photometry. Nitrates and phosphates were determined using UV/Visible spectrophotometry. Fluoride ion selective electrode was used to determine fluoride. The study has shown that there was considerable amount of heavy metals in the water samples of Mathioya River, though the levels were below WHO maximum permissible levels for zinc 0.05 - 0.08, chromium 0.02 - 0.03, lead was below the limit of detection and copper 0.03 - 0.04 while iron 0.73 - 1.16 and manganese 0.88-2.24 mg/L exceeded this limit. The concentrations of the physicochemical parameters pH 6.94 - 7.76, TDS (37.84 - 54.59 mg/L), TSS (42.78 - 53.84 mg/L), DO (4.75 - 8.27 mg/L) and EC 63.89 - 80.17, nitrates (6.40 - 13.66 mg/L), phosphates (0.29 - 0.91 mg/L) and fluoride (0.68 - 0.88 mg/L). Keywords: AAS, AES, UV/VIS, ISE, physico-chemical parameters, nutrients levels, heavy metals

Application of Solid Phase Extraction with Gas Chromatography - Mass Spectrometry in Geographical Profiling and Characterization of Volatile Organics in Kenyan Honey

Honey from different regions fetch different market prices, this makes it prone to mislabeling in terms of origin. This study aimed at identifying markers specific to Kenyan honey from different regions so as to develop a fast reliable profile that can be used in the geographical profiling of honey. Solid-Phase Extraction followed by Gas Chromatography-Mass Spectrometry was used to extract and identify volatile organic compounds in honey from various regions in Kenya. Various volatile organic compounds were identified, they were classified into the following classes; esters, carboxylic acids, aldehydes ketones, and hydrocarbons. It was established that the presence or absence of certain compounds and their variation in concentration can be used to classify honey from different geographical regions in Kenya. Keywords: Honey, Volatile Organics, Gas Chromatography-Mass Spectrometry (GC-MS), Keny

Physicochemical Analysis of Honey in the Kenyan Retail Market

Retail honey has always been subjected to some form of processing during honey production thus its crucial to assess its quality periodically so as to ascertain whether it satisfies the minimum set requirements. This study intended to determine the quality of honey in the Kenyan retail market through physicochemical analysis and comparing them with the set standards by the Kenya Bureau of Standards (KEBS) and International Honey Commission (IHC). Nineteen (19) honey samples both locally produced and imported were obtained from the market; Samples obtained were analyzed following harmonized methods of the International Honey Commission. Even though there was great variation in electrical conductivity, acidity, diastase activity, and HMF Values, results obtained indicated that most of the honey samples met the minimum set requirements. Diastase activity and HMF proved to be the only possible criteria to discriminate between samples which satisfied and those that did not satisfy the minimum set standards. Keywords: Honey, quality, physicochemical analysi

Prospecting For Iron and Titanium Using Termitaria

Mining activities begin with mineral prospecting and exploration, which can be quite expensive.  A number of mineral prospecting methods are known such as excavation of soil for analysis, phyto- prospecting, and hydro-geochemical prospecting among others.  Ants and termites are known to burrow up to 55 meters to water tables. In the process, they bring up debris, which may contain traces of minerals in mineralized areas. Qualitative and quantitative analysis of anthills’ and termite mound soil samples can be used as preliminary tests for prospects of finding a given mineral. Termitaria sampling has been used in other parts of the world such as Australia, India and Ghana. The study sought to find out whether there are significant levels of iron and titanium in anthills soil samples compared to top soil samples from Kwale, Kathwana and Kithiori, which are mineralized areas in Kenya. Flame atomic absorption spectroscopy was used to determine the metals under study after acid digestion. The control samples had lower concentrations of iron for all the three areas; 20.63±0.09 mg/g compared to mean concentration of anthill of 25.3±0.06 mg/g in Kwale, 90.53±0.00 mg/g compared 98.53±0.29 mg/g at Kathwana and 82.63±0.22 mg/g compared to 89.46±0.00 mg/g at Kithiori. Titanium content in termitaria samples was higher than the control for all the three areas; 14.94±0.24 mg/g compared14.72±0.00 mg/g at Kwale, Kithiori18.47±0.03 mg/g compared to15.93±0.03 mg/g at Kithiori and 14.52±0.03 mg/g compared to13.13±0.00 mg/g at Kathwana. These results demonstrate the potential for use of termitaria soil sampling in mineral prospecting. For conclusive results of iron and titanium mineralization, multimedia sampling is recommended. Keywords: Termitaria, Mineral Prospecting, Flame Atomic Absorption Spectroscopy

BIOSORPTION OF SELECTED HEAVY METALS BY THE BIOMASS OF THE GREEN ALGA SPIROGYRA SP.

In this paper, the influence of contact time, initial pH and metal ion concentrations on the adsorption properties of a freshwater green alga (Spirogyra sp.) biomass was studied. Several model solutions of selected heavy metals (Cd, Cu, Cr, Pb) were put into contact with the green algae-based sorbent for different time periods. After the treatment, the concentrations of heavy metals in model solutions were determined using flame atomic absorption spectrometry (FAAS) and inductively-coupled plasma-optical emission spectrometry (ICP-OES). Fourier transform infrared spectroscopy (FTIR) was used to reveal which functional groups were responsible for the green algae biosorption properties. Adsorption capacities were found to be 22.52, 38.19, 35.59 and 94.34 mg/g for Cd, Cr, Cu and Pb, respectively, at contact times of 15-50 minutes and initial metal ion concentrations of 500-700 µg/g. The optimum pH for biosorption of Cd, Cr, Cu and Pb were 5.5, 5.8, 5.9 and 5.0, respectively. The biosorption process followed second order kinetics and fittedthe Langmuir isotherm model. Biomonitoring studies suggested the possible use of this freshwater green algaas a bioindicator, with mean concentration factors for the selected elements in the range of 367-7154. BIOSORPCIJA ODABRANIH TEŠKIH METALA POMOĆU BIOMASE ZELENE ALGE SPIROGYRA sp.   U ovom radu je proučavan uticaj kontaktnog vremena, početnog pH i početne koncentracije metalnih jona na sorpcione karakteristike slatkovodne zelene alge Spirogyra sp. Nekoliko model-rastvora odabranih teških metala (Cd, Cu, Cr, Pb) je tretirano, u različitim vremenskim intervalima, sorbentom pripremljenim od zelenihalgi. Plamena atomska apsorpciona spektrometrija (FAAS) i induktivno kuplovana plazma sa optičkom emisionom spektrometrijom(ICP-OES) su korišćene za određivanje sadržaja teških metala u model-rastvorima Nakon tretmana. Furijeova transformacion ainfracrvena spektroskopija (FTIR) je pokazala koje funkcionalne grupe su nosioci biosorpcionih osobina zelenih algi. Pri kontaktnim vremenima u opsegu 15-50 minuta i polaznoj koncentraciji metala 500-700 µg/ml, sorpcioni kapacitet je iznosio 22,52, 38,19, 35,59 i 94,34 mg/g za Cd, Cr, Cu i Pb. Optimalni pH za biosorpciju Cd, Cr, Cu i Pb je bio 5,5, 5,8, 5,9 i 5,0. Proces biosorpcije prati kinetiku drugog reda i zakonitosti Lengmirovog izotermalnog modela. Rezultati biomonitoringa ukazuju da zelene alge imaju veliki potencijal kao bioindikatori; srednji koncentracioni fakori za proučavane metale su bili u opsegu 367-7154.

Gas diffusion–flow injection interfaces for mass spectrometric and electrochemical detectors

Isotope tracer techniques are widely used in biological, agricultural, chemical and medical research. The use of stable isotopes is not complicated by health hazards, dangers of radiation or time limit for experiments as is the case for radioactive isotopes. However, the analytical methods available for the determination of stable isotopes are much less sensitive, considerably more complicated and time consuming than those for radioactive isotopes. Such methods usually require the use of a mass spectrometer and most employ the combustion technique (Dumas method) for sample presentation. Speciation can be achieved by an isotope ratio mass spectrometer coupled to a gas chromatograph (GC) and combustion interface. Such instruments are expensive and labour intensive. Additionally, the consumables and catalysts employed are costly. [Continues.